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|
set GLOBAL query_cache_size=1355776;
flush query cache;
flush query cache;
reset query cache;
flush status;
drop table if exists t1, t2, t3, t11, t21;
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
create table t2 (a int not null);
insert into t2 values (1),(2),(3);
select * from t1;
a
1
2
3
select * from t2;
a
1
2
3
insert into t1 values (4);
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 2
flush query cache;
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
drop table t1, t2;
create table t1 (a text not null);
create table t11 (a text not null);
create table t2 (a text not null);
create table t21 (a text not null);
create table t3 (a text not null);
insert into t1 values("1111111111111111111111111111111111111111111111111111");
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t11 select * from t1;
insert into t21 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t3 select * from t1;
insert into t3 select * from t2;
insert into t3 select * from t1;
select * from t11;
select * from t21;
show status like "Qcache_total_blocks";
Variable_name Value
Qcache_total_blocks 7
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
insert into t11 values("");
select * from t3;
show status like "Qcache_total_blocks";
Variable_name Value
Qcache_total_blocks 8
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
flush query cache;
show status like "Qcache_total_blocks";
Variable_name Value
Qcache_total_blocks 7
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
drop table t1, t2, t3, t11, t21;
CREATE TABLE t1 ( a INT NOT NULL PRIMARY KEY AUTO_INCREMENT ) ENGINE =
MyISAM;
LOCK TABLE t1 READ LOCAL;
INSERT INTO t1 VALUES (), (), ();
SELECT * FROM t1;
a
SELECT * FROM t1;
a
1
2
3
SELECT * FROM t1;
a
drop table t1;
flush query cache;
reset query cache;
flush status;
create table t1 (s1 int)//
create procedure f1 () begin
select sql_cache * from t1;
select sql_cache * from t1;
select sql_cache * from t1;
end;//
create procedure f2 () begin
select sql_cache * from t1 where s1=1;
select sql_cache * from t1;
end;//
create procedure f3 () begin
select sql_cache * from t1;
select sql_cache * from t1 where s1=1;
end;//
create procedure f4 () begin
select sql_cache * from t1;
select sql_cache * from t1 where s1=1;
select sql_cache * from t1;
select sql_cache * from t1 where s1=1;
select sql_cache * from t1 where s1=1;
end;//
call f1();
s1
s1
s1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 3
show status like "Qcache_inserts";
Variable_name Value
Qcache_inserts 3
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 0
call f1();
s1
s1
s1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 3
show status like "Qcache_inserts";
Variable_name Value
Qcache_inserts 3
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 3
call f1();
s1
s1
s1
select sql_cache * from t1;
s1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 4
show status like "Qcache_inserts";
Variable_name Value
Qcache_inserts 4
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 6
insert into t1 values (1);
select sql_cache * from t1;
s1
1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
show status like "Qcache_inserts";
Variable_name Value
Qcache_inserts 5
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 6
call f1();
s1
1
s1
1
s1
1
call f1();
s1
1
s1
1
s1
1
select sql_cache * from t1;
s1
1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 4
show status like "Qcache_inserts";
Variable_name Value
Qcache_inserts 8
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 10
flush query cache;
reset query cache;
flush status;
select sql_cache * from t1;
s1
1
select sql_cache * from t1 where s1=1;
s1
1
call f1();
s1
1
s1
1
s1
1
call f2();
s1
1
s1
1
call f3();
s1
1
s1
1
call f4();
s1
1
s1
1
s1
1
s1
1
s1
1
call f4();
s1
1
s1
1
s1
1
s1
1
s1
1
call f3();
s1
1
s1
1
call f2();
s1
1
s1
1
select sql_cache * from t1 where s1=1;
s1
1
insert into t1 values (2);
call f1();
s1
1
2
s1
1
2
s1
1
2
select sql_cache * from t1 where s1=1;
s1
1
select sql_cache * from t1;
s1
1
2
call f1();
s1
1
2
s1
1
2
s1
1
2
call f3();
s1
1
2
s1
1
call f3();
s1
1
2
s1
1
call f1();
s1
1
2
s1
1
2
s1
1
2
drop procedure f1;
drop procedure f2;
drop procedure f3;
drop procedure f4;
drop table t1;
reset query cache;
drop function if exists f1;
create table t1 (id int);
create function f1 ()
returns int
begin
declare i_var int;
set i_var = sleep(3);
insert into t1 values(3);
set i_var = sleep(3);
return 0;
end;|
select f1();
select sleep(4);
sleep(4)
0
select * from t1;
id
3
f1()
0
select * from t1;
id
3
reset query cache;
select * from t1;
id
3
drop table t1;
drop function f1;
set GLOBAL query_cache_size=0;
|
